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GENERAL SYSTEM DIAGNOSTICS
SERVICE MANUAL NUMBER 23
90-861326--1 MARCH 1999
Page 5E-3
Scan Tool Normal Specifications (Idle / Warm Engine / Closed Throttle /
Neutral)
SCAN POSITION
UNITS DISPLAYED
TYPICAL DATA VALUE
Memory Calibration Check
Sum
Calibration and Check Sum
Varies with Software revision
in ECM
Oil Press/IO Level (See Note)
OK/LO
OK
Engine Overtemp
OK/Overheating
OK
Lanyard Stop Mode
OFF/ON
OFF
NOTE: MCM will read I/O Level and MIE will read Trans.
MEFI 1 - ECM Connector Chart For 454/502 Mag MPI and 8.2L
MPI
The following chart will aid in diagnosis of symptoms. These voltages were derived from a
known good engine. The voltages shown were done with the electrical system intact and
operational. These are voltage requirements to operate the different circuits.
CAUTION
DO NOT attempt to obtain these voltages by probing wires and connectors. Serious
damage could result in loss of engine operation or wiring damage. Voltages can
vary with battery conditions
J-1
a
J-1 Input Connector (Front)
a -
Shaded Area Denotes Pin Connector Location
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